Spanish researchers make cancer treatment breakthrough

The Plk1 oncogene is found to have positive as well as negative effects

Spanish and German medical researchers have made what is being hailed as an important breakthrough in the field of cancer research, discovering that a gene which for decades has been considered to be favourable for the growth of tumours can in fact have exactly the opposite effect.

The gene labelled Plk1, according to an article published in “Nature Communications” by scientists at the Spanish Centro Nacional de Investigaciones Oncológicas and the German Cancer Research Centre (DKFZ), sometimes actually slows down the growth of cancerous tumours, their conclusion being that the targeting of the gene by some of the pharmaceuticals used in treating cancer needs to be reconsidered.

However, the effect of Plk1 differs among different types of cancer, and even within different sub-types of breast cancer.

The research was based on the fact that the oncogenic nature of Plk1 has never been formally proven, although it is known that it is related to a wide variety of tumours and when its presence is exaggerated this can often lead to a negative outcome. The team thus decided to modify mouse genomes in such a way as to cause over-production of the gene, and the first thing they found was that this did not lead to the modified animals developing more tumours than the control group.

They then crossed their mice with others where breast cancer oncogenes H-Ras and Her2 were already aggressively present, and the result, surprisingly, was that the growth of tumours was halted. In other words, Plk1 is not only an oncogene, but can also act as a tumour suppressor.

When these different roles are fully understood, the hope is that the gene can be used as a part of therapy, rather than being a target for elimination, in the appropriate types of cancer.